Replies

1. 
   Kowboy | Jun 01, 2009 05:30am | #1

   I've never understood the concrete-in-the-hole thing. Dissimilar materials, different expansion and contraction, etc.

   I've always believed in drainage. Why are railroad beds so smooth and immune from frost heave? No footers there. Drainage.

   Put some goo on the buried posts if it makes you feel better, but drop 'em on top of rocks and fill the hole with same.

   Kowboy

1. 
   C1802362 | Jun 01, 2009 05:40am | #2

   Thanks for mentioning the gravel - that's how I put the mailbox in and its been fine for 6 or 7 years.Art

2. 
   husbandman | Jun 01, 2009 06:04am | #3

   Treated will probably last much longer. Kowboy told you correctly, IMO.

   You don't say where you are, but if frost is an issue a post in concrete will likely heavy up over time.

3. 
   MikeHennessy | Jun 01, 2009 03:00pm | #4

   FWIW, after a year, the cedar will be virtually indistinguishable from PT -- both will be grey.

   As others said, set your posts and backfill with gravel. Make sure the holes are deep enough to support the posts, but since you're only using them to hang bird netting, that shouldn't be much.

   Mike Hennessy
   Pittsburgh, PA
   Everything fits, until you put glue on it.

1. 
   darrel | Jun 01, 2009 10:32pm | #6

   The cedar posts will still be straight, though. ;o)

4. 
   PedroTheMule | Jun 01, 2009 06:51pm | #5

   Hi 1802362,

    tar the portion of the posts below grade and just backfill the hole and pack the dirt in

   I had a deck project about 15 years ago and was told "not" to tar the bottom "as any moisture that did wick in could not leave". I thought OK if it can wick in, it can wick out so that didn't make any sense to me. My thinking was that the tar would help reject more moisture and ground critters.

   Anyhow, I double dipped the posts in a roofing tar over a few days a few inches above the point of where the back fill would go. I then wrapped a couple of rounds of heavy plastic around the sides but not the bottom. I wanted any water that did run down the top of the plastic to be able to drain out of the bottom. I poured 2'x2' concrete pads for them to sit on and tapered them center to outside to aid in any drainage and embedded galvanized metal deck blocks in the concrete. Dropped the posts in and allowed them to simply sit in the galavnized blocks. I then back filled with washed #57 stone, topped the fill with plastic sheeting and capped it with pine needles to blend it with the landscaping. The plastic sheeting wrapped around the posts keeps the gravel from cutting through the tar.

   A year ago I got the bright idea to excavate under the deck, suspend galvanize roofing and make a little workshop for garden supplies and the ridin' mower. During the process is was necessary to dig up to the posts and uncover them. I could not find "any" deterioration. They were as solid as the day I planted them. If fact they are in better shape than the painted exposed portion.

   Pedro the Mule - extra work paid off

5. 
   Dinosaur | Jun 02, 2009 02:01am | #7

   If you really want these to be permanent, dig an 8" dia. hole 12" deeper than two-fifths of the height-above-ground of the post. Slide in a Sonotube. Put 12" of 3/4" washed gravel in the bottom of the tube, and tamp it down firmly. Drop a circle of geotextile on top of that.

   Set the post, and brace it plumb with some 1x. Fill around the post with 0-3/4" in 6" lifts, tamping each lift of gravel firmly before adding the next.

   Use cedar.

   Dinosaur

   How now, Mighty Sauron, that thou art not brought
   low by this? For thine evil pales before that which
   foolish men call Justice....